Garden Railway Forum

It’s been a (very) long time since the little Mamod made an appearance on the workbench. Other projects have taken priority but one result of lock down has been extra time spent crossing things off the ‘to do’ list and now I can get back to the interesting stuff!
Rather than working with the original boiler I have treated the patient to a new standard version which along with the new safety valve, sight glass and piston/cylinders assemblies bought some time ago gives me all the bits I need for a running locomotive. I use the term ‘running’ in the loosest possible way.

I’m giving serious consideration to going with a 7/8ths scale narrow gauge on the SM-32 track that I have so I’m investigating the 18” narrow gauge look starting with an extended chimney and basic spectacle plate with no cab roof.

I hope to post some pictures shortly.

Welcome back! I remember lurking this thread years ago, when I briefly owned an MSS. Soon gave up on mine and sold it on. Just went back to the start of the thread and re-read the story thus far. Certainly looking forward to hearing more, as and when.. A 7/8ths conversion would make a particularly interesting model.

Regards,
Aaron

Hi Aaron

Thanks for the comment.

I managed an hour or so working on the loco at the weekend. The new boiler needs its sight glass and back plate installed so I thought it might be a good idea to make a Goodall valve so that I can cold pressure test with just water before trying under steam. I've turned up the valve from 1/4 brass bolt and have an odd bit of normal rubber tube for the cold test but need some silicone stuff for a hot one.

One of the reasons for going with 7/8ths is that the chairperson of the home planning authority has an extensive property portfolio in 1/12th spread around the house so I recon I might get a few 1:13.7 items past the approval stage for use in the garden ! Also I'll be scratch building most of the rolling stock so I'm not relying on the availability of kits or ready to roll items.

I like your thinking.
Funnily enough, I also use a few dolls' house items ('24th scale stuff) in my own work. Certainly a lot of odd detailing parts available, to be adapted to 7/8ths modelling.

Tried a cold pressure test with the new boiler filled to the top with water and my adapted garden spray bottle. No leaks from the sight glass so the next test will be under steam.

To bring things up to date I finally got the locomotive running on a loop of track in the garden. Initially there were issues with steam leaks which were resolved by lapping the steam valve faces and fitting a stronger spring. Next task is to sort out a lubricator and improve the speed control with either a steam valve or exhaust throttle.

Good to see it running, and looking forward to seeing it at the head of a train. Love the 7/8ths extensions so far.

Progress update – taming the beast!

I decided to make a steam turret to go in the rearmost boiler ferrule to provide 4 connections. An extended connection to the cab regulator, a top mounting for the whistle and two side connections, one for a pressure gauge(when funds allow) and the other one for the water filler. It’s a banjo style connection sealed with two ‘o’ rings.

Next task is to route the regulator output pipe via a lubricator to the front control block.

Very nice and neat machine work there.
Grant.